Nitrogen-containing heterocyclic epoxy curing agents, compositions and methods

a technology of nitrogen-containing heterocyclic epoxy and curing agent, which is applied in the direction of epoxy resin coating, coating, organic chemistry, etc., can solve the problems of poor surface defects, greasy surface appearance, and many epoxy coatings that suffer from slow cure, so as to reduce the separation of curing agent and improve the compatibility with epoxy resin , the effect of reducing the separation of curing agent and speeding up the reaction rate of amine-epoxy

Active Publication Date: 2017-05-18
EVONIK OPERATIONS GMBH
View PDF1 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0031]The amine-epoxy curing agent comprising at least one saturated heterocyclic compound having two nitrogen heteroatoms according to formula (I) has better compatibility with epoxy resin, particularly with most common epoxy resins based on bisphenol A or bisphenol F as well as polyepoxy novolac resins. The better compatibility reduces the separation of curing agent from epoxy especially at low temperature. Therefore curing agent and epoxy can react thoroughly and g

Problems solved by technology

However, many epoxy coatings suffer from slow cure at low application temperatures (≦5° C.) and a common side effect of the slow cure is that coatings can develop poor surface defects and a greasy surface appearance referred to as blushing, carbamation of or water spotting.
These problems are in part attributed to the slow amine-epoxy reaction rate and partial incompatibility between the amine curing agent and epoxy resin.
This results in incomplete amine-epoxy reaction and insufficient crosslinking which can lead to poor physical properties and poor coating performance.
If free amine is present on the surface for too long a period, then the amine will react with water and carbon dioxide in the atmosphere and develop a white film on the surface which can lead to poor coating performance.
Another problem is that the cure requires longer time for coating to set and dry, which means l

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Nitrogen-containing heterocyclic epoxy curing agents, compositions and methods
  • Nitrogen-containing heterocyclic epoxy curing agents, compositions and methods
  • Nitrogen-containing heterocyclic epoxy curing agents, compositions and methods

Examples

Experimental program
Comparison scheme
Effect test

examples

[0093]The following synthesis examples are provided to illustrate certain aspects or embodiments of the instant invention and shall not limit the scope of the claims appended hereto.

synthesis examples

[0094]Diethylenetiamine (DETA), formaldehyde aqueous solution were purchase from Aldrich. The reaction product was analyzed by gas chromatography (GC) to determine the amount of unreacted DETA, Metrohm titrator using Karl Fisher titration method for residual water content, Brookfield viscometer for viscosity, Metrohm titrator for amine value, and nuclear magnetic resonance (NMR) for chemical composition. The NMR experiments were performed at ambient temperature employing the Bruker DRX-400 FT-NMR spectrometer equipped with a 10 mm BBO probe. Quantitative 13C NMR data was acquired using inverse-gated decoupling, a 45° pulse, and a 6 second relaxation delay. The samples were dissolved in chloroform-d with chromium acetylacetonate added as a relaxation agent. The chemical shift scale was referenced to the solvent peak. GC analysis was performed on Agilent 7890 Gas Chromatograph equipped with a Agilent CP-Volamine 0.32 mm×30 m—column and a Flame Ionization Detector. The samples were pre...

example 1

Synthesis of Reaction Product of DETA with Formaldehyde at Molar Ratio of 1.25:1 Formaldehyde to DETA

[0095]DETA (250 g, 2.4 mol) was charge to a reactor equipped with a nitrogen inlet, a condenser, an addition funnel, and an overhead stirrer. To DETA was added formaldehyde aqueous solution (245.6 g, 3.0 mol) via an addition funnel to maintain temperature below 60° C. After the addition, the reaction was kept at 60° C. for 30 minutes. Water was then removed under reduced pressure. The product was obtained as a clear liquid in quantitative yield with amine value of 927 meqKOH / g, viscosity of 347 mPa·s at 25° C., water content of 0.41%, and residual DETA of 5.7%. NMR analysis showed that 57 mol % of DETA formed 1-(2-aminoethyl)imidazolidine, which corresponds to 56 wt % to the total weight in the product by calculation.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Temperatureaaaaaaaaaa
Temperatureaaaaaaaaaa
Temperatureaaaaaaaaaa
Login to view more

Abstract

Amine-epoxy curing agents are disclosed including at least one saturated heterocyclic compound having two nitrogen heteroatoms according to formula (I) and at least one saturated fused bicyclic heterocyclic compound having three nitrogen heteroatoms according to formula (II):
wherein X is independently selected from a hydrogen atom, a linear or branched C1 to C4 alkyl group and a substituted or un-substituted phenyl group, Y1 is a direct bond or a divalent polyethylene polyamine group having 1 to 8 nitrogen atoms or a divalent polyethylene polyamine derivative having 1 to 8 nitrogen atoms, Y2 is a direct bond or a divalent polyethylene polyamine group having 1 to 7 nitrogen atoms and R is independently a hydrogen atom or a group selected from C1-C8 linear, cyclic, and branched alkyl, alkenyl, and alkaryl groups.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application claims priority from U.S. Ser. No. 62 / 256,262 filed Nov. 17, 2015 having the same title, which is incorporated herein by reference in its entirety.BACKGROUND OF THE INVENTION[0002]The present invention is directed to nitrogen-containing heterocyclic epoxy curing agents, compositions, and methods.[0003]Epoxies are known for their excellent adhesion, chemical and heat resistance. In addition they also have good-to-excellent mechanical properties, and good electrical insulating properties. Cured epoxy resin systems are found in an extensive range of applications within the coatings, adhesives, and composites markets. Specific examples include epoxy composite using carbon fiber and fiberglass reinforcements, structural adhesives, protective coatings for metal surface, and construction products for concrete, cementitious or ceramic substrates, often referred to as civil engineering applications such as formulations for concret...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C08G59/50C08G59/60C08G59/56C07D233/02C09D163/00
CPCC08G59/5073C07D233/02C08G59/60C08G59/56C09D163/00C08G59/508C07D487/08C08G59/502C08G59/5086C08K5/3445C08K5/3472
Inventor ZHENG, SHIYINGANANTHACHAR, SUDHIRFAZEL, SHAFIQ NISARALICOOK, MICHAEL IANRASING, ROBERT MARJO THEODOORCAO, WEITIJSMA, EDZE JAN
Owner EVONIK OPERATIONS GMBH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap